Need to convert new drive to GPT but....

One of my 2TB drives on a 6 drive machine needs to be replaced with a larger 3TB drive as it is nearly full. I'm running Windows 7 Pro x64 and the catch 22 is the drive needing replacement is not the boot drive.
According to MS (http://technet.microsoft.com/library/cc725671.aspx) the boot drive will also need to be GPT to allow mixing of GPT & MBR disks on the same computer. Is there a work around or a way to change the boot drive (C) to GPT without losing all? Any suggestions?
Thanks

It is the capability and compatibility of the OS and mobo drivers that allow native use of non-system GPT disks. Win 7 64 bit is compatible, no problem, just change the 3TB disk to GPT when no partitions are established, partition as you will and move over to it if that's where the current 2TB drive's data is going.
I'm using a couple external 3TB drives with 32-bit XP (loaded with MBR disks), it should not be an issue for you. Continue using the boot drive just the way it is.

My second question is how to get back to the original disk management scene where the disk looks undivided. It displayed the undivided disk and asked for initialization. I did not initialize and and was reading the screen when it changed to divided 2.2TB x .768TB. I did not initialize or format.

Well the fix turned out to be simpler than I imagined. I updated the chipset drivers and the BIOS and on reboot and a trip to the disk management console the option to turn the 3TB drive to GPT appeared. No 3rd party disk tools required. I thought I had all the latest drivers but Asus snuck a couple in on me.
Thank you so much for all the help! It made me think.................